Background: Clinical and experimental data clearly indicate a correlation between new blood vessel formation, metastatic spread and aggressiveness of ovarian cancer. Currently, the development of these vessels can be studied with the use of color Doppler sonography or by measurements of several specific factors involved. Potential serum markers may include angiogenin (ANG) and vascular endothelial growth factor (VEGF), both of which have been identified as important angiogenesis modulators. Objective: We sought to investigate whether a combination of serum angiogenin and VEGF levels along with several currently used grayscale criteria and color Doppler blood flow assessment can be useful in preoperative discrimination of ovarian tumors. Methods: Patient's age, menopausal status, ultrasound gray-scale and color Doppler sonography combined with serum CA-125 (Roche, Switzerland) antigen and two cytokines: angiogenin and VEGF (R&D Systems, USA) measurements were evaluated in women who were subsequently operated because of adnexal tumors. Logistic regression analysis was then used to determine which of the 14 independent variables had prognostic significance in the constructed predictive model. Results: There were 65 benign and 13 (3 stage I) malignant tumors in 78 patients. Median serum values in benign tumors were as follows: ANG -410,8 pg/mL (range: 98,3-956,3 pg/mL), VEGF-274,3 pg/mL(range: 52,1-1142,O pg/mL); CA-125 -20,3 IU/ml (range 3,1-999,3 IU/ml). Median serum concentrations in women with malignant tumors were as follows: ANG -469,l (range: 65,3-1103,O pg/mL), VEGF-365,4 pg/mL (range: 67,4-1243,l pg/mL); CA-125 -88,l IU/ml (range 8-943 IU/ml). A logistic regression analysis revealed that the important prognostic factors included: patient's age and menopausal status, presence of papillary projections in the tumor wall, color Doppler vascularity assessment and resistive index measurements. Other variables appeared to be non-predictive. Conclusion: Angiogenin and vascular endothelial growth factor serum measurements do not seem to add prognostic value to the established sonographic criteria of ovarian malignancy.